General

First thing- run a complete scan with your regular, updated, Anti-Virus scanner. Then run a complete scan with an updated "Malwarebytes Anti-Malware".
Viruses and spyware can really slow your computer down if there are any hiding in the system.

Next thing, do some basic disk maintenance to tune up your hard drive-
(Do these things in this order)

First open the Control Panel, then "Add or Remove Programs".
Go down the list and look for things that you no longer use or need. Uninstall any you don't want any more.

Next open "My Computer", then RIGHT-click on the C: drive and select "Properties" from the popup menu.
On the "Properties" page click the "Tools" tab.
On the "Tools" tab click the "Check Now" button.
On the popup, check the top box, then click "OK".
If it says Windows is using the files and asks if you want to run the disk check when Windows starts, say Yes, then restart the computer.

This will scan the hard drive looking for file system errors and fixing any it can.

Next open "My Computer", then RIGHT-click on the C: drive and select "Properties" from the popup menu.
Click the "Disk Cleanup" button under the big "pie chart".
It will scan the hard drive looking for old junk, Windows log files, installation files, stuff that's just taking up wasted space on the hard drive.
When it finishes scanning check all the boxes in the popup and say "OK"

This will scan and remove any wasted space on the hard drive.

Next open "My Computer", then RIGHT-click on the C: drive and select "Properties" from the popup menu.
On the "Properties" page click the "Tools" tab.
Click the "Defragment Now" button.
On the defragment page click the C: drive to highlight it, then click "Defragment". This will take a long time to complete.

This will scan the hard drive and rearrange files which are broken up and put all the pieces back together to make the hard drive run at its best performance.

Do these steps in order because each builds on what the previous one did.
Do these things about once a month to keep the hard drive running at its best.

Next thing to try, find your Broadband Modem. It may NOT be the "router" with the wireless antennas on it, it may be a separate box.
You're looking for the box that connects to the telephone jack on the wall, or the Cable TV cable.
Unplug the power connector from the back of the Modem and wait a few seconds. Then plug the power connector back in.
This will reset the modem and make it re-connect to your ISP which may give you a better (faster) connection.

These are just some basic things you can do to help your computer run better and hopefully improve your Internet connection speed.